玉米直链淀粉生物合成多基因转化载体构建  

Construction of Multiples Genes Transformation Vector for Improving Linear Starch Biosynthesis of Maize

作　　者：郭美娜[1] 孙丽芳[1] 杨光[1] 邹宏达[1] 苏胜忠[1] 吴颖[1] 原亚萍[1] 

机构地区：[1]吉林大学植物科学学院,长春130062

出　　处：《生物技术通报》2010年第12期103-109,共7页Biotechnology Bulletin

基　　金：国家转基因生物新品种培育重大专项(2009ZX08003-024B)

摘　　要：淀粉分支酶基因sbe是影响玉米直链淀粉含量的主要因素,淀粉分支酶分为3种即sbeI、sbeIIa和sbeIIb,其中sbeIIb对直链淀粉含量影响效应最大,抑制玉米淀粉分支酶sbeIIb基因的表达可减少支链淀粉的含量,从而达到提高直链淀粉的目的;ADP-葡萄糖焦磷酸化酶(AGPase)是直链淀粉合成的关键酶,通过提高AGP表达量同样可提高玉米直链淀粉含量。以此为目的分别克隆了sbeIIb一段375bp高度保守区,玉米SBE基因一段175bp内含子,AGP完整开放阅读框,大麦胚乳特异启动子和ADPG基因终止子。构建了sbeIIb基因正、反义的hpRNA发夹结构,将该发夹结构与上述基因分别连接到pCAM-BIA3301上;构建得到包含sbeIIb基因干扰结构与AGP基因过表达的pCAMB-RSA多基因胚乳特异表达载体。为此,pCAMB-RSA载体的成功构建将为高直链淀粉玉米的培育奠定基础。The mainly factors,effecting the synthesis of linear starch,is starch branching enzymes（SBE）genes,including sbeI,sbeIIa and sbeIIb.However,the most effection one of them is sbeIIb.Accordingly,one feasible way to prompt the accumulation of linear starch is to inhibit the expression of sbeIIb.ADP-glucose pyrophosp horylase polypeptide（AGPase）is also the key gene for liner starch biosynthesis,therefore,the accumulation of linear starch would be improved if the AGP expression increased.In the experiments,these genes,one 375 bp sequence from the highly conservation area of sbeIIb,intron（about 175 bp）from SBE,AGP including ORF,barely endosperm specific promoter and ADPG terminator were cloned and constructed into pCAMBIA3301 vector for the purpose of rising linear starch accumulation.The recombinant pCAMB-RSA vector includes hpRNA structure of a sbeIIb gene and the over expression AGP gene at the same time.The construction of the pCAMB-RSA vector is the basis for further studying the highly linear starch content characteristic of maize.

关 键 词：玉米 直链淀粉 HPRNA ADP-葡萄糖焦磷酸化酶 sbeIIb基因 

分 类 号：S513[农业科学—作物学]